Removal of crystal violet and methylene blue from aqueous solutions by activated carbon prepared from Ferula orientalis

Abstract

Ferula orientalis L. stalks were used as an agricultural solid biomass waste for preparation of activated carbon with zinc chloride activation using slow pyrolysis in a fixed-bed reactor. The chemical characteristics of the activated carbon obtained at 550°C were identified by elemental, fourier transform infrared spectroscopy, Brunauer-Emmett-Teller, scanning electron microscopy analyses and found to have a surface area of 1,476 m 2 /g. The ability of the activated carbon to adsorb methylene blue and crystal violet from aqueous solutions has been investigated. Adsorption studies were performed at different initial dye concentrations (200-800 ppm), contact time (0.5-90 min) and temperature (25-45°C). Adsorption data were modeled with Langmuir, Freundlich and Temkin adsorption isotherms. Equilibrium data of the adsorption processes showed that adsorption of methylene blue is fitted to the Langmuir and crystal violet to the Freundlich isotherm. Pseudo-first-order, pseudo-secondorder and Elovich kinetic models were used to analyze the kinetic data obtained at different initial dye concentrations. The adsorption kinetic data were very well described by the pseudo-second-order model. The calculated thermodynamic parameters such as change in free energy, enthalpy and entropy showed that adsorptions of both dyes onto activated carbon were spontaneous and endothermic under the experimental conditions.

Removal of NO2 by carbonaceous adsorbents obtained from residue after supercritical extraction of marigold

“…One of the most effective methods for elimination of pollutants is their adsorption by activated carbons (Bansal and Goyal 2005;Guo et al 2013;Nowicki et al 2013). Thanks to their strongly developed porous structure, activated carbons show very good sorption properties, from both liquid and gas phase and that is why they have been applied in many areas (Aysu and Küçük 2015;Kazmierczak et al 2013;Nowicki et al 2008). Continuous broadening of the range of their use leads to increased demands for activated carbon adsorbents, which stimulates the search for new carbon precursors.…”

Malachite green removal using modified sphagnum peat moss as a low-cost biosorbent: Kinetic, equilibrium and thermodynamic studies

“…To evaluate the kinetic mechanism of the adsorption process, the pseudo-first-order, pseudo-second-order and intra-particle diffusion models were applied to test the experimental data [26,27].…”

“…The adsorption equilibrium was evaluated using the Langmuir, Freundlich and Temkin isotherm models [11,26,28].…”

Adsorption of malachite green and crystal violet cationic dyes from aqueous solution using pumice stone as a low-cost adsorbent: kinetic, equilibrium, and thermodynamic studies

“…Among these dyes, MG and CV cationic dyes are carcinogenic, genotoxic, mutagenic, and teratogenic compared to anionic dye due to their synthetic origin and aromatic ring structure with delocalized electrons [5,6]. As most of these organic dyes in industrial effluents are damaging living aquatic organisms, therefore, it is very necessary to remove dyes from industrial effluents before it is discarded into the aquatic environment [7].…”